The present invention relates to a transparent conductive composition, a transparent conductive layer formed of the same and a manufacturing method thereof, and more particularly, to a composition for a transparent conductive layer used as an anti-static layer and an electromagnetic wave shielding layer of home appliances, and a power supplying transparent electrolyte of a flat panel display, a transparent conductive layer formed of the composition and a manufacturing method thereof.
A transparent conductive layer is a thin layer formed on the surface of an insulation material layer having high light transmittance. The transparent conductive layer includes a metal thin film of platinum (Pt) or gold (Au) and a metal oxide thin film of indium tin oxide (ITO), tin oxide, titanium oxide or antimony oxide.
Generally, the transparent conductive layer is manufactured by a sputtering method, a deposition method or an ion beam method. When intending to form the transparent conductive layer by one of the above methods, a high-price equipment such as vacuum device is required, increasing the manufacturing costs. Also, since the manufacturing process by the above method is performed under a vacuum condition, the size of a thin film to be manufactured is severely limited.
To solve the above problems, a method for manufacturing a transparent conductive layer has been suggested, which includes the steps of coating a dispersion containing transparent conductive particles on a substrate to form a conductive layer, and then forming a protective layer made of a hydrolyzed product of a metal alkoxide on the resultant structure. The structure of the transparent conductive layer formed by the above method is shown in FIG. 1.
Referring to FIG. 1, transparent conductive particles 14 of the conductive layer 12 formed on a substrate 11 do not directly contact each other and void is existed in space between the transparent conductive particles 14. Here, reference numeral 13 represents the protective layer made of a hydrolyzed product of a metal alkoxide.
However, a solvent used in manufacturing the transparent conductive layer partially remains in the void. The void between the transparent conductive particles increase contact resistance of the transparent conductive layer, thereby lowering the conductivity of the layer.
In order to obtain a transparent conductive layer having excellent conductivity, it is necessary to perform a high-temperature (400xc2x0 C. or more) sintering process under a reduction atmosphere. However, it is difficult to apply this method adopting the high-temperature sintering process to articles that have poor heat-resistance such as plastics, and the method may damage a coating equipment, causing difficulties in practical use.
It is an object of the present invention to provide a composition for a transparent conductive layer having excellent conductivity.
It is another object of the present invention to provide a transparent conductive layer having excellent conductivity, transmittance and hardness.
It is still another object of the present invention to provide a manufacturing method of the transparent conductive layer.
To achieve the first object, there is provided a transparent conductive composition comprising transparent conductive particles; metal alkoxide [M1(OR)4]; metal (M2) particles or salt thereof (M2X); and a catalyst,
wherein the metal alkoxide [M1(OR)4] is one selected from the group consisting of Si(OR)4, Ti(OR)4, Sn(OR)4 and Zr(OR)4, where R is C1-C4 alkyl, and the metal (M2) is at least one selected from the group consisting of silver (Ag), gold (Au), platinum (Pt), copper (Cu), nickel (Ni), lead (Pb), cobalt (Co), rhodium (Rh), ruthenium (Ru) and tin (Sn), and X is one selected from the group consisting of chloride, nitrate and sulfonate.
To achieve the second object, there is provided a transparent conductive layer comprisng transparent conductive particles, a hydrolyzed product of metal alkoxide [M1(OR)4] and metal (M2) particles, wherein the metal alkoxide [M1(OR)4] is one selected from the group consisting of Si(OR)4, Ti(OR)4, Sn(OR)4 and Zr(OR)4, where R is C1-C4 alkyl, and the metal (M2) is at least one selected from the group consisting of silver (Ag), gold (Au), platinum (Pt), copper (Cu), nickel (Ni), lead (Pb), cobalt (Co), rhodium (Rh), ruthenium (Ru) and tin (Sn).
To achieve the third object, there is provided a method for manufacturing a transparent conductive layer comprising the steps of:
(a) coating a first composition containing a transparent conductive particle on a substrate; and
(b) coating a second composition containing a metal alkoxide [M1(OR)4]; metal (M2) particles or salt thereof (M2X); and a catalyst on the resultant, and drying and heating the resultant,
wherein the metal alkoxide [M1(OR)4] is one selected from the group consisting of Si(OR)4, Ti(OR)4, Sn(OR)4 and Zr(OR)4, where R is C1-C4 alkyl, and the metal (M2) is at least one selected from the group consisting of silver (Ag), gold (Au), platinum (Pt), copper (Cu), nickel (Ni), lead (Pb), cobalt (Co), rhodium (Rh), ruthenium (Ru) and tin (Sn), and X is one selected from the group consisting of chloride, nitrate and sulfonate.